org.apache.lucene.search.BitsFilteredDocIdSet Maven / Gradle / Ivy
package org.apache.lucene.search;
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.util.Objects;
import org.apache.lucene.util.Bits;
/**
* This implementation supplies a filtered DocIdSet, that excludes all
* docids which are not in a Bits instance. This is especially useful in
* {@link org.apache.lucene.search.Filter} to apply the {@code acceptDocs}
* passed to {@code getDocIdSet()} before returning the final DocIdSet.
*
* @see DocIdSet
* @see org.apache.lucene.search.Filter
*/
public final class BitsFilteredDocIdSet extends FilteredDocIdSet {
private final Bits acceptDocs;
/**
* Convenience wrapper method: If {@code acceptDocs == null} it returns the original set without wrapping.
* @param set Underlying DocIdSet. If {@code null}, this method returns {@code null}
* @param acceptDocs Allowed docs, all docids not in this set will not be returned by this DocIdSet.
* If {@code null}, this method returns the original set without wrapping.
*/
public static DocIdSet wrap(DocIdSet set, Bits acceptDocs) {
return (set == null || acceptDocs == null) ? set : new BitsFilteredDocIdSet(set, acceptDocs);
}
/**
* Constructor.
* @param innerSet Underlying DocIdSet
* @param acceptDocs Allowed docs, all docids not in this set will not be returned by this DocIdSet
*/
public BitsFilteredDocIdSet(DocIdSet innerSet, Bits acceptDocs) {
super(innerSet);
this.acceptDocs = Objects.requireNonNull(acceptDocs, "Bits must not be null");
}
@Override
protected boolean match(int docid) {
return acceptDocs.get(docid);
}
}